Tandem bicycles have a frame on which are mounted a front ground engaging wheel that is steerable by the captain of the bicycle who is positioned at the front thereof, and a rear ground engaging wheel that is driven by the captain using a front pedal system and by a stoker, positioned rearwardly of the captain, using a rear pedal system. Each of the pedal systems includes a shaft rotatably mounted in a hub carried by the frame. Connected to the axial ends of each shaft are pedal cranks that terminate in pedals by which a user inputs pedaling motion to rotate the shaft.
Conventionally, the shafts of the front and rear pedal systems are connected to the driven wheel of the bicycle by a transmission system that operates to couple the front pedal system to the rear pedal system. As a consequence, pedal input by the riders is not independent. That is to say, one rider is unable to terminate pedaling if the other chooses to continue. Moreover, the transmission system usually includes a gear changing mechanism, to establish the mechanical advantage between the pedal system and the driven wheel. Such mechanism is usually under the exclusive control of the captain. As a result, the mechanical advantage achieved with the gear changing mechanism is the same for each rider and is thus independent of their physical abilities which may be significantly different. Consequently, riders with different physical abilities, or endurance, or stamina cannot be accommodated with a conventional transmission system.
It is therefore an object of the present invention to provide a new and improved transmission system for tandem bicycles which overcomes or substantial ameliorates the deficiencies of the prior art as described above.